usb: chipidea: imx: simplify the usbmisc callers

Move struct imx_usbmisc_data NULL pointer judgement from caller to
each API, it can simplify the caller.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index 9385602..eb77e32 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -265,8 +265,12 @@
 
 int imx_usbmisc_init(struct imx_usbmisc_data *data)
 {
-	struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
+	struct imx_usbmisc *usbmisc;
 
+	if (!data)
+		return 0;
+
+	usbmisc = dev_get_drvdata(data->dev);
 	if (!usbmisc->ops->init)
 		return 0;
 	return usbmisc->ops->init(data);
@@ -275,8 +279,12 @@
 
 int imx_usbmisc_init_post(struct imx_usbmisc_data *data)
 {
-	struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
+	struct imx_usbmisc *usbmisc;
 
+	if (!data)
+		return 0;
+
+	usbmisc = dev_get_drvdata(data->dev);
 	if (!usbmisc->ops->post)
 		return 0;
 	return usbmisc->ops->post(data);